Ong Seong-wu

Despite being an acting trainee, Ong was sent as a representative by his company to participate in Produce 101 (season 2) due to his well-rounded skills in singing and dancing.[7] He achieved an 'A' rank in the evaluations, and went on to finished fifth place in the finale with 984,756 votes. As part of the top eleven contestants, he would go on to debut as a member of Wanna One.[1]

Prior to his participation in Produce 101, Ong took part in a short film project Short Film Project: Beginning. The short film, titled Seong-wu Is Alright, was released on June 19, 2017.[8][9] Additionally, he also made a special appearance on the mobile drama Idol Fever, which aired between July 7 to July 17, 2017.[10]

Ong debuted as a member of the project group Wanna One on August 7, 2017.[11] He went on to represent the group in several appearances on variety shows such as Happy Together, The Return of Superman, and Saturday Night Live Korea.[12][13][14] He also served as a special emcee on music show broadcasts for M Countdown and Inkigayo.[15][16] Ong, together with fellow group mate Kang Daniel, was cast for the pilot episode of the variety show Master Key, and was later confirmed as a fixed cast member.[17] His appearance on the show garnered positive reactions from media outlets, receiving praise for his skilful deception of his cast mates in the psychological game-style show to net the show's biggest win thus far.[18][19]

In November, Ong featured in singer Huh Gak's music video for his digital single "Only You".[20]

In February 2018, Ong was named one of the main emcees of Show! Music Core. He subsequently left his position in September 2018.[21] He also continued appearing on several variety shows. He appeared on Living Together in Empty Room with Kang Daniel and Kim Jae-hwan,[22] and also became a cast member of the reality show Law of the Jungle Sabah, which aired from July 27, 2018 to September 21, 2018.[23]

His contract with Wanna One ended on December 31, 2018, however he continued to appear with the group until its official farewell concerts on January 24–27, 2019.[24]

Upon conclusion of his activities with Wanna One, Ong embarked on his first solo fan-meeting tour, titled "Eternity", in March and April 2019.[25] On March 7, 2019, he was also named PR Ambassador of the Incheon Metropolitan City Office of Education.[26]

As part of Pepsi and Starship Entertainment's 2019 Pepsi K-Pop Collab Project, Ong released the single "Heart Sign".[27] The track was written by producers Flowblow, who penned Wanna One's hit debut single, "Energetic".[28] The music video was released on June 11, 2019.[29]

Ong made his acting debut in the later half of the year, starring as the male lead in JTBC's youth drama At Eighteen, alongside Kim Hyang-gi and Shin Seung-ho.[30] The drama tackles some of the issues faced by youths in South Korea, such as first love, the pressures of school and parental expectation, to topics such as school violence and bullying. Ong played the role of transfer student Choi Jun-woo, who is falsely accused of school violence.[31] He garnered many positive reviews for his emotive acting,[32] and went on to nab several awards for the role, including Best Rookie Award and Hallyu Star Award at the Korea Drama Awards.[33] Ong also recorded the song "Our Story" as part of the official soundtrack for the drama, which was released on August 8, 2019.[34]

In January 2020, Ong kicked off his second solo fan-meeting tour, titled "We Belong". Beginning in South Korea, the tour was set to span cities in several countries including Thailand, Taiwan and the Philippines.[35] The digital single "We Belong" was released on January 9.[36] Intended as a fan-song, Ong participated in both the lyric writing and composition of the single,[37] and performed it on the first time during the Seoul leg of his tour on January 11.[38]

Ong appeared on the second season of travel variety show, Traveler, with fellow actors Ahn Jae-hong and Kang Ha-neul. The variety show focused on the backpacking travels of the trio in Argentina, and began airing starting February 15.[39] He went received much attention for his photography skills on the first episode.[40]

Ong made his comeback as a singer with his first solo album, Layers.[41] The EP was released on March 25,[42] together with lead single, "Gravity".[43] Ong took part in the composition and lyric writing of all the songs on the album, drawing his inspiration from his emotions and stories from the past year.[44]

He also made several appearances on variety shows, including Omniscient Interfering View,[45] as well as Master in the House,[46] Radio Star,[47] and Running Man.[48] He also featured on You Hee-yeol's Sketchbook, performing his new single and displaying his drumming skills on the show's live music format.[49]

Ong collaborated with singer Baek Ji-young on duet, "Didn't Say Anything". The ballad was released on May 12.[50]

Ong is set to star as the male lead in the JTBC drama Number of Times Friends Become Lovers, alongside Shin Ye-eun and Kim Dong-jun. He will play photographer Lee Soo. The drama airs in the later half of 2020.[51]

Furthermore, Ong will also be making his film debut in the upcoming musical-movie, Life is Beautiful, starring Ryu Seung-ryong and Yum Jung-ah. He is set to play Ryu's younger counterpart in the film. The film goes to theatres later this year.[52]